Pattern Generator – Create Custom Text Patterns & Templates

Generate random strings from custom patterns using a simple bracket syntax. Define ranges like [a-z], [A-Z], [0-9], integer ranges like [100-200], or pick from a custom list like [cat,dog,bird]. Mix literal characters (commas, dashes, spaces) freely between tokens. Generate multiple results at once and use preset templates to get started instantly. Perfect for creating random usernames, codes, IDs, test data, and more — entirely in your browser.

Quick-start templates

31 chars
[A-Z][0-9][0-9]-[a-z][a-z][a-z]
Results

Token syntax reference

[a-z]Random lowercase letter (a through z)
[A-Z]Random uppercase letter (A through Z)
[0-9]Random single digit (0 through 9)
[100-200]Random integer in range, inclusive
[a,b,X,7,@]Pick one item from the list — strings, emojis, anything
[f]Literal value — list with one item, always returns it
literalAny character outside [ ] appears exactly as typed

How to Use the Pattern Generator

Features:

  • Define ranges like [a-z], [A-Z], [0-9] in patterns.
  • Use integer ranges like [100-200] or custom lists like [cat,dog,bird].
  • Mix literal characters freely between tokens.
  • Generate multiple results at once with preset templates.

How to use:

  1. Enter a pattern using bracket tokens or select a preset template.
  2. Set the number of results to generate.
  3. Click Generate to create random strings.
  4. Click Copy to copy results, or Clear to start over.

Tips:

  • All processing runs entirely in your browser — your data never leaves your device.
  • Works instantly with no server requests or API calls.